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1.
J Hazard Mater ; 382: 121023, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476717

RESUMO

Pesticide residues pose a great threat to human health, and it is an urgent matter to realize fast and accurate detection of pesticide. SERS (Surface Enhanced Raman Scattering), as a nondestructive detection technology, performs a prominent role in fast detection field due to the strong surface plasmon resonance from short range effect between analyte and nanoparticle. Therefore, in order to solve the incompatibility between organochlorine pesticides molecules and noble metal nanoparticles, this paper proposed a concept of "bridge" substances acting as an interconnect function role to achieve a binding model (object-binder-metal (OBM)) and developed a droplet concentration method to enhance Raman signals. Both combination mode of pesticide molecules to bridge molecules and energy transfer of SERS experiment may relate to the compound ring according to the changes of peaks based on surface plasmon resonance. The selectivity and stability of different bridge substances interacting with pesticides molecules were illumined via binding energy of these two substances obtained by DFT calculations. A droplet can capture nanoparticles and analytes, which is conducive to SERS performance. Chloride ions in the solution contribute to rearrangement of nanoparticles and can validly promote surface activation of Ag nanoparticles to improve energy transfer efficiency of plasma resonance, resulting in superior SERS effect.

2.
Food Chem ; : 125575, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31685369

RESUMO

Recent reports showed that patients could be sensitized to fish tropomyosin (TM), who exhibited clinical symptoms. However, little information is available on differences in TM immune cross-reactivity among fish, shrimp and clam. Moreover, allergenicity might change during the food processing owing to the change of protein structure. In this study, we developed a nonthermal extraction technique to purified TM, IgG/IgE binding, cross-reactivity and structures were compared. Results showed that raw and boiled fish-TM were not cross reactive and had weak recognition of shrimp, while, shrimp-TM and clam-TM were cross reactive. The ELISA further confirmed that fish-TM was not able to trigger allergic immune response in shrimp sensitive subjects, while, surface hydrophobicity of fish-TM was higher. The study demonstrated that fish-TM, being with high sequence similarity, did not have cross-reactivity with shrimp and clam-TM. They could have a variable degree of IgE binding depending on subject sensitivity and allergenicity.

3.
Nat Genet ; 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578528

RESUMO

Elevated serum urate levels cause gout and correlate with cardiometabolic diseases via poorly understood mechanisms. We performed a trans-ancestry genome-wide association study of serum urate in 457,690 individuals, identifying 183 loci (147 previously unknown) that improve the prediction of gout in an independent cohort of 334,880 individuals. Serum urate showed significant genetic correlations with many cardiometabolic traits, with genetic causality analyses supporting a substantial role for pleiotropy. Enrichment analysis, fine-mapping of urate-associated loci and colocalization with gene expression in 47 tissues implicated the kidney and liver as the main target organs and prioritized potentially causal genes and variants, including the transcriptional master regulators in the liver and kidney, HNF1A and HNF4A. Experimental validation showed that HNF4A transactivated the promoter of ABCG2, encoding a major urate transporter, in kidney cells, and that HNF4A p.Thr139Ile is a functional variant. Transcriptional coregulation within and across organs may be a general mechanism underlying the observed pleiotropy between urate and cardiometabolic traits.

4.
Nanoscale ; 11(39): 18329-18337, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31573590

RESUMO

The sustainable production of H2 fuel via the hydrogen evolution reaction (HER) using low-cost catalysts to replace expensive noble metals is highly desired. Here using first-principles calculations, we design a delicate monolayer transition metal compound, Ni-MoS2, consisting of orderly interlaced Ni and Mo metal ions, and investigate its HER catalytic performance. The Gibbs free energy, ΔGH, which is the best descriptor for the HER, is calculated and optimized with respect to strain and S vacancies. Remarkably, the calculated ΔGH is found to be ∼0 eV at the biaxial strain of 11%-12%, which is superior to MoS2, for which straining alone is insufficient to achieve the optimal performance. We further reveal that along with straining, the bandgap is reduced and a semiconductor-to-metal transition is induced, leading to an enhancement in the charge transfer and HER performance. Moreover, ΔGH ≈ 0 eV is achieved at the S vacancy concentration of only ∼2.5%, which is in strong contrast to ∼12.5% required for MoS2. We further show that the defective Ni-MoS2 is able to enhance the conductivity, which leads to the reduction of ΔGH. Two remarkable HER mechanisms and alkaline HER kinetics have been demonstrated in this study: perfect Ni-MoS2 prefers the Volmer-Heyrovsky mechanism in the strain state, whereas the Volmer-Tafel mechanism is more preferred for the defective Ni-MoS2. The kinetic energy barrier of the alkaline HER is reduced, revealing that Ni-MoS2 promotes the rate-determining water dissociation step. The present work suggests that the designed monolayer Ni-MoS2 compound significantly outperforms MoS2 in terms of HER activity, and thus is promising for low-cost, pH-universal and high-performance HER applications.

5.
J Chem Phys ; 151(14): 144702, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615224

RESUMO

Carrier scattering processes are studied in CH3NH3PbI3 using temperature-dependent four-wave mixing experiments. Our results indicate that scattering by ionized impurities limits the interband dephasing time (T2) below 30 K, with strong electron-phonon scattering dominating at higher temperatures (with a time scale of 125 fs at 100 K). Our theoretical simulations provide quantitative agreement with the measured carrier scattering rate and show that the rate of acoustic phonon scattering is enhanced by strong spin-orbit coupling, which modifies the band-edge density of states. The Rashba coefficient extracted from fitting the experimental results (γc = 2 eV Å) is in agreement with calculations of the surface Rashba effect and recent experiments using the photogalvanic effect on thin films.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31612643

RESUMO

AIM: Immune suppression based on alternative regulation of immune checkpoint proteins, for example, programmed cell death receptor-1 (PD-1) and cytotoxic T lymphocyte-associated molecule-4 (CTLA-4), which results in T-cell exhaustion, contributes to cancer development and progression. In this study, we sought to characterize the distribution of CTLA-4 and T-cell lymphocyte activation gene-3 (LAG-3) expression on exhausted T cells in different T-cell subsets from patients with acute myeloid leukemia (AML). METHODS: The coexpression of CTLA-4 and LAG-3 on exhausted CD244+ and CD57+ T cells from the CD3+ , CD4+ , and CD8+ T-cell subsets in peripheral blood from 12 patients with newly diagnosed AML was analyzed by multicolor flow cytometry assay. RESULTS: A significantly higher percentage of CTLA-4+ CD3+ , CD4+ and CD8+ T cells was found in patients with AML. In addition, higher numbers of both CTLA-4+ CD244+ and CTLA-4+ CD57+ CD3+ T cells were detected. Interestingly, the increased CTLA-4+ CD244+ T cells were predominantly CD4+ T cells. In contrast, the increased CTLA-4+ CD57+ T cells primarily consisted of the CD8+ T-cell subset. A high proportion of LAG-3+ T cells was found in only a few cases with AML; however, a significantly higher proportion of coexpression of CTLA-4 and LAG-3 in the CD3+ and CD8+ T-cell subsets was detected. CONCLUSION: We for the first time observed higher CTLA-4+ CD244+ CD4+ , CTLA-4+ CD57+ CD8+ , CTLA-4+ LAG-3+ CD3+ and CTLA-4+ LAG-3+ CD8+ T cells in patients with AML, whereas the upregulated expression of LAG-3 on T cells was only found in a subset of the cases. These data may provide further information by complementing the heterogeneity of immune checkpoints expression in AML.

7.
Phys Chem Chem Phys ; 21(40): 22293-22301, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31576823

RESUMO

Self-trapped excitons (STEs) in two-dimensional (2D) hybrid organic-inorganic perovskites (HOIPs) emit broadband white light, suggesting the great potential of 2D HOIPs in low-cost lighting and display applications. A prerequisite for understanding STEs' properties is a correct identification of the underlying interaction that leads to the STEs. Here, we show that the long-range polar coupling between electrons and optical phonons is quenched in 2D HOIPs' tightly bound excitons and cannot effect STEs. Rather, the STEs are induced by a short-range optical deformation potential (ODP) arising from the phonon-modulated Pb-X quantum-well thickness. Interaction between transition dipoles in adjacent PbX6 (X = Br or I) octahedra gives rise to highly anisotropic intra- and inter-layer exciton bandwidths. In flat (001) 2D HOIPs, both the ODP and the exciton bandwidths are susceptible to out-of-plane PbX6 tilting but not to the in-plane one, and their interplay can quantitatively account for the observed temperature and structure dependences of luminescence associated with STEs. In corrugated (011) 2D HOIPs, the exciton bandwidth is further reduced and the resultant STEs have a stronger lattice distortion and broader luminescence spectrum. Our results reveal the mechanism of STE formation and suggest ways of tuning STEs and associated broadband luminescence in 2D HOIPs.

8.
Anal Bioanal Chem ; 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31620825

RESUMO

Surface-enhanced Raman spectroscopy (SERS) has the potential to detect pesticide residues in agricultural products. However, some systemic pesticides, such as chlorpyrifos, can enter the plant tissue, and not just stay on the surface. Consequently, many SERS studies halted at practical application because of its complexity. In this work, SERS technology was used to detect chlorpyrifos residues in tea products at the semiquantitative level. A simple pretreatment method effectively avoided interference of other fluorescent substances, and all major peaks could be distinguished on the basis of a novel substrate. A principal component analysis algorithm was applied to form a regression model, and a nanogram detection limit was obtained. Furthermore, chlorpyrifos residues in the same tea products were also measured by gas chromatography-mass spectrometry, and the results show a small range of errors. From the comparative study of the two detection methods, the results suggest the great promise of SERS technology for rapid inspection of agricultural products.

9.
Org Lett ; 21(19): 7692-7696, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31524406

RESUMO

An originally designed Rh-catalyzed [4 + 2] cycloaddition reaction of nitrogen-tethered 1,7-ene-dienes turned out to be a cycloisomerization reaction, which involves allylic C-H activation/alkene insertion into Rh-H bond/reductive elimination processes. Deuterium labeling experiments gave support to the proposed mechanism. This unexpected cycloisomerization reaction provides an efficient way to synthesize trans-divinylpiperidines from easily accessed linear 1,7-ene-dienes.

10.
Chem Commun (Camb) ; 55(80): 12012-12015, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31538167

RESUMO

A new type of zwitterionic nitrosoalkene generated in situ from dehydrohalogenation of α-halo-N-alkylhydroxamic acids was designed. [4+2] cycloadditions of this heterodiene to olefins provide a facile route to construct six-membered heterocycles containing an N-O bond and a new protocol for 1,2-syn carbohydroxylate alkenes with a hydroxyl and acetamide group. DFT calculations support a concerted cycloaddition pathway and the solvent HFIP can stabilize the transition state through H-bonding interaction.

11.
Phytomedicine ; 64: 153084, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31514083

RESUMO

BACKGROUND: Metastasized melanoma is extremely difficult to treat. Activation of C-C chemokine receptor type 7 (CCR7) has been linked to melanoma metastasis. CCR7 can be directly regulated by miR-let-7. We have previously shown that an ethanolic extract of an herbal formula comprising Sophorae Flos and Lonicerae Japonicae Flos (SLE) inhibits melanoma cell migration and invasion. PURPOSE: In this study, we determined whether SLE suppresses melanoma metastasis, and whether regulation of miR-let-7a/f-CCR7 signaling is involved in the effect. STUDY DESIGN AND METHODS: Small RNA sequencing was conducted to compare miRNA expression profiles of B16F10 tumors dissected from SLE-treated or untreated mice. Western blot and RT-qPCR analyses were employed to examine protein and miRNA levels, respectively. A B16F10 melanoma lung metastasis mouse model was used to evaluate the effects of SLE on melanoma metastasis. MiR-let-7a/f-knockdown and CCR7-overexpression cell models were used to investigate the involvement of miR-let-7a/f-CCR7 signaling in the anti-metastatic effects of SLE. RESULTS: It was found that SLE upregulated levels of miR-let-7a/f in B16F10 melanoma tissues. SLE significantly elevated levels of miR-let-7a/f, lowered the protein level of CCR7, inhibited the phosphorylation of CCR7 downstream molecules p38 and JNK in B16F10 and A375 melanoma cells. SLE inhibited B16F10 melanoma lung metastasis in mice. SLE upregulated levels of miR-let-7a/f, and lowered protein levels of CCR7, MMP-2, MMP-9, phospho-p38 (Thr180/Tyr182) and phospho-JNK (Thr183/Tyr185) in melanoma-invaded lung tissues. Knockdown of miR-let-7a/f diminished the effects of SLE on CCR7 signaling in, and invasion of, melanoma cells. Overexpression of CCR7 lessened the effects of SLE in inhibiting the phosphorylation of p38 and JNK in, and the invasive capability of, melanoma cells. CONCLUSION: We for the first time demonstrated that SLE inhibits melanoma metastasis in mice, and that regulation of the miR-let-7a/f-CCR7 pathway contributes to the anti-metastatic mechanisms of SLE. These findings provide a pharmacological basis for developing SLE as a modern agent for treating metastatic melanoma. Additionally and importantly, this study suggests that regulating the miR-let-7a/f-CCR7 pathway is a novel strategy for controlling melanoma metastasis.

12.
Steroids ; 152: 108499, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31536733

RESUMO

A series of new cinnamic acid-pregenolone hybrids (5a-5o) was designed, synthesized and evaluated for their in vitro antiproliferative activity. Some of them showed potential antiproliferative activity and selectivity towards a panel of cancer cell lines, including A549, H157, HepG2, MCF-7, and HL-60. Among these analogs, compound 5f showed the most promising activity with IC50 values ranging from 3.2 to 6.8 µM, and it was taken as a model compound in the following antiproliferative mechanism study. In Hoechst 33258 staining assay, 5f-treated A549 cells displayed significant apoptosis characteristics. Flow cytometry analysis revealed that 5f showed the antiproliferative activity against A549 via G1 cell cycle arrest and inducing apoptosis. Western blotting analysis demonstrated that 5f enhanced apoptosis of A549 cells by down-regulating Bcl-2 and up-regulating Bax protein expression. The present study highlighted this series of cinnamic acid-pregenolone hybrids as a new antiproliferative lead prototype.

13.
Mod Pathol ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31485011

RESUMO

Localized malignant mesotheliomas (LMM) is an uncommon and poorly recognized neoplasm. Its pathologic diagnosis is often surprising in patients with serosal/subserosal based localized tumors that are clinically suspicious for metastatic lesions or primary sarcomas. Once a tumor is diagnosed as "mesothelioma", LMM is often mistaken for diffuse malignant mesothelioma (DMM). Best currently available evidence about LMM was collected from the literature and cases diagnosed by members of the International Mesothelioma Panel (IMP). One hundred and one (101) LMM have been reported in the English literature. Patients had localized tumors with identical histopathologic features to DMM. Patients ranged in age from 6 to 82 years; 75% were men. Most (82%) of the tumors were intrathoracic. Others presented as intrahepatic, mesenteric, gastric, pancreatic, umbilical, splenic, and abdominal wall lesions. Tumors varied in size from 0.6 to 15 cm. Most patients underwent surgical resection and/or chemotherapy or radiation therapy. Median survival in a subset of patients was 29 months. Seventy two additional LMM from IMP institutions ranged in age from 28 to 95 years; 58.3% were men. Sixty tumors (83.3%) were intrathoracic, others presented in intraabdominal sites. Tumors varied in size from 1.2 to 19 cm. Median survival for 51 cases was 134 months. Best evidence was used to formulate guidelines for the diagnosis of LMM. It is important to distinguish LMM from DMM as their treatment and prognosis is different. A multidisciplinary approach is needed for the diagnosis of LMM as it shows identical histopathology and immunophenotype to DMM.

14.
Nat Commun ; 10(1): 4130, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511532

RESUMO

Increased levels of the urinary albumin-to-creatinine ratio (UACR) are associated with higher risk of kidney disease progression and cardiovascular events, but underlying mechanisms are incompletely understood. Here, we conduct trans-ethnic (n = 564,257) and European-ancestry specific meta-analyses of genome-wide association studies of UACR, including ancestry- and diabetes-specific analyses, and identify 68 UACR-associated loci. Genetic correlation analyses and risk score associations in an independent electronic medical records database (n = 192,868) reveal connections with proteinuria, hyperlipidemia, gout, and hypertension. Fine-mapping and trans-Omics analyses with gene expression in 47 tissues and plasma protein levels implicate genes potentially operating through differential expression in kidney (including TGFB1, MUC1, PRKCI, and OAF), and allow coupling of UACR associations to altered plasma OAF concentrations. Knockdown of OAF and PRKCI orthologs in Drosophila nephrocytes reduces albumin endocytosis. Silencing fly PRKCI further impairs slit diaphragm formation. These results generate a priority list of genes and pathways for translational research to reduce albuminuria.

15.
Molecules ; 24(17)2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31461873

RESUMO

Seven rare e:b-friedo-hopane-type triterpenoids including four new (1-4) and three known (5-7) ones with 5 being first reported as a natural product, together with five other known triterpenoids (8-12), were isolated from the nonpolar fractions of the ethanolic extract of Euphorbia peplus. Structural assignments for these compounds were based on spectroscopic analyses and quantum chemical computation method. The structural variations for the C-21 isopropyl group, including dehydrogenation (1 and 3) and hydroxylation at C-22 (simiarendiol, 2), were the first cases among e:b-friedo-hopane-type triterpenoids. Simiarendiol (2) bearing a 22-OH showed significant cytostatic activity against HeLa and A549 human tumor cell lines with IC50 values of 3.93 ± 0.10 and 7.90 ± 0.31 µM, respectively. The DAPI staining and flow cytometric analysis revealed that simiarendiol (2) effectively induced cell apoptosis and arrested cell cycle at the S/G2 phases in a dose-dependent manner in HeLa cells.

16.
Pathol Res Pract ; 215(10): 152553, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31362888

RESUMO

BACKGROUND: Nidogen-2 (NID2) is a ubiquitous component in the basement membrane and plays an important role in the development of malignant tumors. However, the specific function and mechanism of the NID2 gene in gastric cancer remains unclear. In this study, we aimed to investigate the role of NID2 in gastric cancer(GC). METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of NID2 in 67 GC tissues and adjacent normal tissues. The relationship between NID2 expression and clinicopathological features was further analyzed. In addition, we evaluated the expression of NID2 in GC based on data from the GEPIA and Kaplan-Meier Plotter database and compared the database results with our own experimental results. Invasion and wound healing assays were used to detect the function of NID2 in MKN45 and SGC7901 cells. Finally, the NID2 network and its possible related genes are constructed by the bioinformatics framework. RESULTS: The expression level of NID2 was found to be significantly over-expressed in gastric cancer cells and tissues compared with normal controls and positively associated with TNM stage, showing a poor prognosis of GC patients. In vitro experiments indicated that NID2 was able to promote the ability of invasion and migration in GC cells. Bioinformatics prediction showed NID2 might regulate the progression of GC via protein digestion and absorption, amoebiasis, PI3K-AKt-signaling pathway, focal adhesion and ECM-receptor interaction pathways. CONCLUSION: Our study demonstrates that up-regulated NID2 plays an important role in promoting the invasion and migration of GC cells and has a potential of being a novel biomarker for diagnosis, treatment and prognosis of GC in the future.

17.
Mol Pharmacol ; 96(5): 589-599, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31462456

RESUMO

Licorice is a medicinal herb widely used to treat inflammation-related diseases in China. Isoliquiritigenin (ISL) is an important constituent of licorice and possesses multiple bioactivities. In this study, we examined the selective anti-AML (acute myeloid leukemia) property of ISL via targeting FMS-like tyrosine kinase-3 (FLT3), a certified valid target for treating AML. In vitro, ISL potently inhibited FLT3 kinase, with an IC50 value of 115.1 ± 4.2 nM, and selectively inhibited the proliferation of FLT3-internal tandem duplication (FLT3-ITD) or FLT3-ITD/F691L mutant AML cells. Moreover, it showed very weak activity toward other tested cell lines or kinases. Western blot immunoassay revealed that ISL significantly inhibited the activation of FLT3/Erk1/2/signal transducer and activator of transcription 5 (STAT5) signal in AML cells. Meanwhile, a molecular docking study indicated that ISL could stably form aromatic interactions and hydrogen bonds within the kinase domain of FLT3. In vivo, oral administration of ISL significantly inhibited the MV4-11 flank tumor growth and prolonged survival in the bone marrow transplant model via decreasing the expression of Ki67 and inducing apoptosis. Taken together, the present study identified a novel function of ISL as a selective FLT3 inhibitor. ISL could also be a potential natural bioactive compound for treating AML with FLT3-ITD or FLT3-ITD/F691L mutations. Thus, ISL and licorice might possess potential therapeutic effects for treating AML, providing a new strategy for anti-AML.

18.
World J Gastroenterol ; 25(29): 3956-3971, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31413530

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a common chronic non-organic disease of the digestive system. Berberine (BBR) has been used to treat patients with IBS, but the underlying therapeutic mechanism is little understood. We believe that BBR achieves its therapeutic effect on IBS by preventing stress intestinal inflammation and visceral hypersensitivity and reducing bowel motility. AIM: To test the hypothesis that BBR achieves its therapeutic effect on IBS by preventing subclinical inflammation of the intestinal mucosa and reducing visceral hypersensitivity and intestinal motility. METHODS: IBS was induced in rats via water avoidance stress (WAS). qRT-PCR and histological analyses were used to evaluate the levels of cytokines and mucosal inflammation, respectively. Modified ELISA and qRT-PCR were used to evaluate the nuclear factor kappa-B (NF-κB) signal transduction pathway. Colorectal distention test, gastrointestinal transit measurement, Western blot, and qRT-PCR were used to analyze visceral sensitivity, intestinal motility, the expression of C-kit (marker of Cajal mesenchymal cells), and the expression of brain derived neurotrophic factor (BDNF) and its receptor TrkB. RESULTS: WAS led to mucosal inflammation, visceral hyperalgesia, and high intestinal motility. Oral administration of BBR inhibited the NF-κB signal transduction pathway, reduced the expression of pro-inflammatory cytokines [interleukin (IL)-1ß, IL-6, interferon-γ, and tumor necrosis factor-α], promoted the expression of anti-inflammatory cytokines (IL-10 and transforming growth factor-ß), and improved the terminal ileum tissue inflammation. BBR inhibited the expression of BDNF, TrkB, and C-kit in IBS rats, leading to the reduction of intestinal motility and visceral hypersensitivity. The therapeutic effect of BBR at a high dose (100 mg/kg) was superior to than that of the low-dose (25 mg/kg) group. CONCLUSION: BBR reduces intestinal mucosal inflammation by inhibiting the intestinal NF-κB signal pathway in the IBS rats. BBR reduces the expression of BDNF, its receptor TrkB, and C-kit. BBR also reduces intestinal motility and visceral sensitivity to achieve its therapeutic effect on IBS.

19.
Inorg Chem ; 58(16): 10829-10836, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31368693

RESUMO

Developing noble-metal-based catalysts with ultralow loading to achieve excellent performance for selective hydrogenation of alkynes under mild reaction conditions is highly desirable but still faces huge challenges. To this end, a SO3H-anchored covalent organic framework (COF-SO3H) as the support was deliberately designed, and then ultralow-content Pd (0.38 wt %) was loaded by a wet-chemistry immersion dispersion method. The resulting Pd0.38/COF-SO3H composite exhibits outstanding performance for the selective hydrogenation of phenylacetylene with 97.06% conversion and 93.15% selectivity to styrene under mild reaction conditions (1 bar of H2, 25 °C). Noticeably, the turnover frequency value reaches as high as 3888 h-1, which outperforms most of reported catalysts for such use. Moreover, such a catalyst also exhibits excellent activity for a series of other alkynes and high stability without obvious loss of catalytic performance after five consecutive cycles.

20.
J Cardiovasc Nurs ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31373957

RESUMO

BACKGROUND: The hypertension control rate in China is much lower than that in developed countries. Self-management among elderly patients with hypertension can improve blood pressure control; thus, it is necessary to explore its association with individual and social environmental factors. OBJECTIVE: Our objective was to investigate self-management among elderly patients with hypertension in China and its association with individual and social environmental factors based on the social ecological model. METHODS: A total of 301 elderly patients with hypertension were recruited to do a questionnaire survey based on the social ecological model, which included the General Demographic Information Questionnaire, Hypertension Patients Self-Management Behavior Rating Scale, World Health Organization Well-Being Index, Family APGAR Index, and Social Support Rating Scale. RESULTS: The lowest level of self-management behaviors was in exercise management, and the highest was in medication management. The results of multiple linear regression analysis showed that well-being, family function, sex, education level, and age were pivotal individual and social environmental factors influencing self-management behaviors among elderly patients with hypertension. CONCLUSIONS: There is a need to develop and test interventions that improve self-management in elderly patients with hypertension. Specifically, individualized interventions to promote exercise among elderly persons with hypertension who are single and living alone are needed. Male patients with a lower education level, poor well-being, poor family function, and the lowest self-management levels are a key population to target.

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